Drug-naive patients with Parkinson's disease in Hoehn and Yahr stages I and II show a bilateral decrease in striatal dopamine transporters as revealed by [123I]beta-CIT SPECT.
Ten healthy subjects and 16 patients with early Parkinson's disease (PD) were examined with single photon emission computed tomography (SPECT) and [123I]beta-CIT, a ligand for the dopamine (DA) transporter. Only drug-naive patients were examined since the expression of and binding to DA transporters may be influenced by dopaminergic medication. The main finding was a significant reduction in [123I]beta-CIT binding in the ipsi- and contralateral striatal regions, especially in the putamen, which showed a mean reduction of 65% of the control mean. Discriminant function analysis of the putaminal [123I]beta-CIT binding measures classified 100% of the cases in the correct group. Disease severity correlated negatively and highly significantly with the binding measures. Tremor ratings did not correlate with the SPECT measures, whereas rigidity, and to a lesser extent bradykinesia, did. Patients with unilateral PD showed a bilateral loss of striatal DA transporters. Our findings indicate that with [123I]beta-CIT SPECT it is possible to diagnose PD in subjects with very mild symptoms and signs. Moreover, finding a bilateral loss of striatal DA transporters in patients with unilateral PD also suggests that it may be possible to identify subjects in the preclinical phase of the disease.
Tissingh
G
G
Academisch Ziekenhuis Vrije Universiteit, Department of Neurology, Amsterdam, The Netherlands.
Bergmans
P
P
Booij
J
J
Winogrodzka
A
A
van Royen
E A
EA
Stoof
J C
JC
Wolters
E C
EC
D000328:Adult; D000368:Aged; D002352:Carrier Proteins / Q000378:metabolism*; D016022:Case-Control Studies; D003042:Cocaine / Q000031:analogs & derivatives; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism*; D016002:Discriminant Analysis; D018450:Disease Progression; D004298:Dopamine / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010300:Parkinson Disease / Q000188:drug therapy / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D002352:Carrier Proteins; D050483:Dopamine Plasma Membrane Transport Proteins; D007457:Iodine Radioisotopes; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C069723:2beta-carbomethoxy-3beta-(4-iodophenyl)tropane; D003042:Cocaine; D004298:Dopamine